1. Field of the Invention
The present invention relates to a pulse wave detection device and a method of detecting a pulse wave. More specifically, the present invention relates to a pulse wave detection device and a method of detecting a pulse wave wherein a pulse wave is detected with selection of a pressure sensor for pulse wave detection from a plurality of pressure sensors.
2. Description of the Invention
A pulse wave is detected based on pressure information which is a voltage signal obtained from a pressure sensor pressed against a surface over an artery of a living body. For accurate detection of the pulse wave, a plurality of pressure sensors are utilized and the pulse wave is measured based on the pressure information from an optimum pressure sensor which is located above a central portion of an artery.
A pressure pulse wave detection device is conventionally known which uses a multiplexer to multiplex pressure information obtained from a plurality of pressure sensors into a signal line for detection (see Japanese Patent Laying-Open No. 06-114018). With a multiplexer as such, a number of lines between pressure sensors and A/D (Analog/Digital) converters as well as a number of A/D converters can be decreased.
In a conventional pulse wave detection device, however, since pressure information is obtained with switching among the plurality of pressure sensors using the multiplexer to select an optimum sensor, a noise cannot be sufficiently eliminated to ascertain a characteristic of a waveform when the pulse wave is to be measured after selection of the optimum sensor.